Galbraith's railway mail service maps, Minnesota.
One of eight large-scale pictorial maps of midwestern states showing routes and post offices of the Railway Mail Service. Designed by Chicago railway mail clerk Frank H. Galbraith to help employees of the Railway Mail Service quickly locate counties and post offices. The maps were rented for practicing or prospective workers who numbered over 6,000 and traveled over a million miles a year on...
Galbraith, Frank H. - United States. Railway Mail Service